Wait, when you say "web ide", do you mean "to make web projects" or do you mean "web-based ide"?
That is a really interesting question.
For 1: If you have no money try NetBeans / Eclipse. In my experience eclipse can be a pain in the ass if you need certain plugins etc. Sometimes you have to search the web for repo-adresses that are compatible with your IDE-version and the other plugins and if you don't use a new version you may have trouble installing plugins from the marketplace. NB is pretty good for open source software and I prefer it to Eclipse.
If you have the money / are a student (who don't have to pay), just use WebStorm / IntelliJ Idea. It is a really superior IDE and you don't want to use anything else once you tried the integration / workflow with it, it's just beautiful how things 'just work'.
For 2: I checked out codio, but the price is really expensive and I'd rather use intelliJ etc. Depending on what you want to write something like Firefox Web IDE doesn't look that bad (https://developer.mozilla.org/en/docs/Tools/WebIDE). For the web I think the best thing would be to port atom.io to a webApp. This would be the next awesome thing ;-)